Modifier and Type | Method and Description |
---|---|
protected static <INKEY,INVALUE,OUTKEY,OUTVALUE> |
Task.createReduceContext(Reducer<INKEY,INVALUE,OUTKEY,OUTVALUE> reducer,
org.apache.hadoop.conf.Configuration job,
TaskAttemptID taskId,
RawKeyValueIterator rIter,
Counter inputKeyCounter,
Counter inputValueCounter,
RecordWriter<OUTKEY,OUTVALUE> output,
OutputCommitter committer,
StatusReporter reporter,
org.apache.hadoop.io.RawComparator<INKEY> comparator,
Class<INKEY> keyClass,
Class<INVALUE> valueClass) |
Modifier and Type | Method and Description |
---|---|
protected void |
Reducer.cleanup(Reducer.Context context)
Called once at the end of the task.
|
protected void |
Reducer.reduce(KEYIN key,
Iterable<VALUEIN> values,
Reducer.Context context)
This method is called once for each key.
|
void |
Reducer.run(Reducer.Context context)
Advanced application writers can use the
Reducer.run(org.apache.hadoop.mapreduce.Reducer.Context) method to
control how the reduce task works. |
protected void |
Reducer.setup(Reducer.Context context)
Called once at the start of the task.
|
Modifier and Type | Method and Description |
---|---|
void |
ValueAggregatorReducer.reduce(org.apache.hadoop.io.Text key,
Iterable<org.apache.hadoop.io.Text> values,
Reducer.Context context) |
void |
ValueAggregatorCombiner.reduce(org.apache.hadoop.io.Text key,
Iterable<org.apache.hadoop.io.Text> values,
Reducer.Context context)
Combines values for a given key.
|
void |
ValueAggregatorReducer.setup(Reducer.Context context) |
Modifier and Type | Method and Description |
---|---|
void |
ChainReducer.run(Reducer.Context context) |
protected void |
ChainReducer.setup(Reducer.Context context) |
Modifier and Type | Method and Description |
---|---|
void |
FieldSelectionReducer.reduce(org.apache.hadoop.io.Text key,
Iterable<org.apache.hadoop.io.Text> values,
Reducer.Context context) |
void |
FieldSelectionReducer.setup(Reducer.Context context) |
Modifier and Type | Class and Description |
---|---|
class |
WrappedReducer.Context |
Modifier and Type | Method and Description |
---|---|
Reducer.Context |
WrappedReducer.getReducerContext(ReduceContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT> reduceContext)
A a wrapped
Reducer.Context for custom implementations. |
Modifier and Type | Method and Description |
---|---|
void |
IntSumReducer.reduce(Key key,
Iterable<org.apache.hadoop.io.IntWritable> values,
Reducer.Context context) |
void |
LongSumReducer.reduce(KEY key,
Iterable<org.apache.hadoop.io.LongWritable> values,
Reducer.Context context) |
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